1. Field of the Invention
Aspects of the invention relate to an apparatus and a method to display an availability of a wireless local area network (LAN), and, more particularly, to an apparatus and a method to display an availability of a wireless LAN, in which information about an area supporting a wireless LAN is provided to a user carrying a mobile phone in the form of text, voice, or images.
2. Description of the Related Art
A wireless local area network (LAN) such as 802.11, 802.11a, 802.11b, and 802.11g are wireless network standards that transmit data at 11 to 54 Mbps using the Ethernet protocol, in particular, a Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) protocol, for route sharing. In addition to an 802.11-based wireless LAN, an 802.16e-based wireless network has been developed. The “WiBro (wireless broadband)” is an Internet service that uses frequencies in the 2.3 GHz band to provide mobility at more than 60 km/hr and transmission speeds equivalent to 1 Mpbs. Since the maximum propagation distance of WiBro is 48 km, its service coverage is 10 times larger than a wireless LAN, which is available only in a service area called a hot spot.
A laptop or a personal digital assistant (PDA) participating in a wireless network is referred to as a station that can exchange data with other stations or connect to the Internet by connecting to an access point (AP) that is a bridge between the wired domain and the wireless domain. A user who desires to use a wireless network can connect to a LAN using a mobile phone network. The wireless network using the mobile phone network, in which a base station relays connections between a wireless domain and a wired domain, allows users within the area of the mobile phone network to use the wireless network, but typically is expensive to use.
FIG. 1 illustrates a connection to a LAN using a conventional wireless network. A wireless LAN 11, which provides a wireless network service using an access point (AP) that is a bridge between a wired domain and a wireless domain, is widely used among wireless networks to connect to a LAN 10. The wireless LAN 11 is typically not expensive to use, but its AP generally has a narrow propagation distance.
A WiBro 12, to provide a wireless network service using a radio access station that bridges a wireless domain and a wired domain, is a domestic portable Internet service based on IEEE 802.16e. The WiBro 12 typically has an advantage of a wider propagation distance over the wireless LAN 11. A mobile phone network 13, to provide a wireless network service using a base station that bridges a wireless domain and a wired domain, allows a terminal within the propagation distance of a base station, such as the cell area of the base station, to connect to the LAN 10 and can provide a seamless network service during movement between cells.
The mobile phone network 13 generally has higher mobility and wider propagation distance than the WiBro 12, but is usually expensive to use. Thus, most users primarily use the wireless LAN 11. With the commercialization of the WiBro 12, widespread use of the WiBro 12 is expected to occur. However, a user who desires to connect to a wireless network using a user terminal, such as a laptop or a PDA, can experience difficulty in recognizing whether a wireless network service, such as the wireless LAN 11 or the WiBro 12, is available in its current location. In this regard, the user typically visually checks to see if an AP or a radio access station is located nearby or use the user terminal to check if an AP or a radio access station is accessible. Such checking to determine if an AP or a radio access station is accessible is usually inconvenient and often requires having to wait for completion of booting after turning on the terminal.
Korean Unexamined Patent Publication No. 2004-0000213 discloses an Internet connecting method with a user's terminal using a heterogeneous network as a connection network, in which a search is made to determine a network environment available in a user's current location. The disclosed technique checks if a wireless LAN to provide a wireless LAN service or a code division multiple access (CDMA) service is available in the user's current location, and then provides one of the wireless LAN service and the CDMA service according to the check result of the service availability. Since the disclosed technique checks if a wireless LAN is supported near or around the user's current location and then provides an available network service, the user can unintentionally use a mobile communication network that has relatively high charges in view of a lack of information about the availability of the wireless LAN, such as after short-range movement by the user.